UI: cannot change file selection after highlighting a file

[wilke]

Description

In the BV-BRC workspace file browser, once a file is highlighted (selected), clicking on a different file does not change the selection. The original file remains highlighted and the user cannot switch to another file without a workaround.

Steps to reproduce

1. Open the file selection dialog (e.g. when choosing an input FASTA file)
2. Click on a file to highlight/select it
3. Click on a different file

Expected

The highlight moves to the newly clicked file.

Actual

The first file remains highlighted. Clicking another file has no effect.

Priority

Medium — blocks normal file selection workflow; users cannot correct a wrong selection without restarting the dialog.